A biochemical examination of blood is generally conducted on plasma or serum as a subject. Plasma is prepared by collecting about 10 mL of venous blood by a syringe and centrifuging the venous blood. In an immune examination of an item relating to infectious diseases, serum is used as a measuring sample, but at least about 30 minutes of treatment time for separating serum, which is the sum of a time for solidifying blood and a time for the subsequent centrifugation, is required for obtaining serum from whole blood.
Therefore, medical staffs require great care and time, and this is sometimes harmful to the life of a patient especially in an emergency case such as a cardiac disease. Furthermore, in an emergency operation in which an immediate judgment to determine whether or not a patient has an infectious disease such as hepatitis or HIV is required, the development of a more rapid measuring method in which an examination time from after collection of blood is shorten has been desired.
Examples of immune assays include a radioimmunoassay (RIA), an enzyme immunoassay (EIA), a particle agglutination process, a counting immunoassay and the like, and in RIA and EIA, it is necessary to conduct an antigen-antibody reaction and then conduct B/F separation, and thus great care and time are required until a measuring result is obtained.
Conventionally, in carrying out an immunoassay intended for an antigen and the like in blood, a sample in which a certain defined amount of plasma or serum accounts for 100% is envisaged. Therefore, in the case of a sample containing blood cell components such as whole blood, the serum or plasma component to be measured is apparently small (35 to 65% of whole blood differs in cell components in individuals). Accordingly, in conventional methods, a measurement value of an antigen or the like contained in blood is corrected and a final quantification value is calculated in some cases with consideration for the amount of the above-mentioned blood cell components, but it has not been carried out until now to apply the exemplary embodiments of other steps to the case when a sample containing blood cell components such as whole blood is used.
Patent Literature 1 suggests an automatic analyzer having a washing function, which can retain the state of the automatic analyzer always constant by monitoring the state of the automatic analyzer and automatically determining the degree of washing by reflecting the state.
This automatic analyzer is an automatic analyzer that can automatically conduct an analysis and can conduct washing motions, and includes a measurement result monitoring means for monitoring at least one of items of change in a water blank value, stability of a reagent blank value and an analysis result of a control subject among measurement results of a light absorbance measuring unit, and a washing condition determination means for determining a washing condition from the result of the measurement result monitoring means and a standard value. Therefore, the invention is an invention that pays an attention to contamination among samples with consideration for sample crosstalk during continuous measurement of samples, and is required in an apparatus to which an immobilized dispenser nozzle is adopted. However, various means used for such automatic analyzer are not disclosed as means for use in conducting an immunoassay using a sample containing blood cell components such as whole blood.